class Container {
    static of(value){
        return new Container(value)
    }
    constructor(value){
        this._value = value 
    }
    map(fn){
        return Container.of(fn(this._value))
    }
}
class MayBe {
    static of(x){
        return new MayBe(x)
    }
    isNothing(){
        return this._value === null || this._value === undefined
    }
    constructor(x){
        this._value = x
    }
    map(fn){
        return this.isNothing() ? this : MayBe.of(fn(this._value))
    }
}

module.exports = { MayBe, Container}